Impact crusher



July 6, 1937.

O. C. GRUENDER IMPACT CRUSHER Filed'sept. 15, 1935 2/.9 -I

7 Sheets-Sheet l July 6 1937 o. c. GRUENDER 2,086,383

IMPACT CRUSHER Filed sept. 1:5, 19:55 v'sneets-sheet l2' IMPACT CRUSHERFiledvsept. 1s, 195s T Sheets-,Sheet 3 6 6. rd w92 wif/*mw Q Wm @6 Ml fim@ f mar 0 l ,WV .M 9 ,.lv .a a a \J w f Q s z July 6, 1937.

O. C. GRUENDER IMPACT CRUSHER Filed Sept. 13, 1935 '7 Sheets-Sheet 4IMPACT CRUSHER Filed sept. 13,'1955 '7 SheetsfSheet 5 July 6, 1937.

o. c. GRUENDER A 2,086,383

IMPACT CRUSHER y. Filed sept. 13, lss 7 sheets-sheet e Patented July 6,1937' UNITED STATES maar caUsnEn Oscar C.

Gruender, Milwaukee, Wis., assignor to Nordberg Manufacturing o.',Milwaukee, Wis., a corporation of Wisconsin 'Application September 13,1335, Serial No. 40,430

10 Claims.

My invention relates to an improvement in impact` crushers. One purposeis the provision of an impact crusher having a low power consumption.Another purpose is the provision of a compact and unitary apparatuswhich will occupy a minimum of space. Another object is to avoid the useof reduction gears or belts. Another object is the construction of ahousing with provision for ready access to impeller and breaker platesas well as to liners. Anotherl object is to provide several means forthe attachment of breaker plates to the impeller, whereby the breakerplates are easily applied or removed and firm- 1y held. Another objectis the provision of the use of breaker plates at such an angle as tocause the particles to be thrust against the liners or in-4 terceptingplates along a horizontal direction, thereby increasing the impactingeffect. Another object is the prevention of the entry of dust into themain shaft bearings. Other objects will apfication and claims.

I illustrate my invention more or'less diagramnatically in theaccompanying drawngs,'where "Figure 1 is a plan view;

Figure 2 is a section on the line 2--2 of Figure l; K

Figure 3 is a section onthe line 3-3 of Figure 1;

Figure 4 is a section on the line 4-4of Figure 2; l

Figure 5 is a section on the line 5-5 of Figure 4;

ure 3; Figure 7 is a horizontal section through a variant form ofthedevice;

Figure 8 is a plan view of a further variation; Figure 9 is a section onthe line 9-9 of Figure 8;

Figure 10 is a partial section on the line Ill-I0 of Figure 9;

Figure 11 is a vertical section with partsbroken away, illustrating-astill further variation of the device; I

Figure 12 is a horizontal diagrammatic section of another modified form;

Figure 13 is a partial side view with the crushing bowl in section, of astill further variation;

I l y 14 is a diagrammatic horizontal section ofthe device illustratedin Figure 13.

Like' parts are indicated by llike symbols 55j Atlmznx'g'liout 'thespecification and drawings.

pear from time to time in the course of the speci- 4 Figure 6 is asection on the line 6 6 of Figi'A .f terial 21 Referring for example tothe form of Figures 1 and 2, I generally indicates any suitable basevupon which is mounted a circumferential frame member herein illustratedas in the form of a channel?, with a bottom flange -3 engaging the baseI and a top ange 4 to which may be bolted a supporting plate or spider 5having a. central sleeve 6. Mounted upon the upper flange 1 of thiscentral sleeve 6 is a generally cylindrical motor housing 8. The detailsof the motor do not of themselves form part of the present invention butI indicate an impellerrotor shaft generally as 9. which, it will beunderstood, may be directly coupled to the motor, so that notransmission, gearing, belts, or separate driving means are necessary.I8 is any suitable upper housing or cover which shields the motor. andmotor bearings.

It rests upon the upper flange of the member 8. It is shown herein ashaving ears II which support the generally vertical rods I2 upon theupper ends of which is mounted a hopper or feed box I3 aligned with anysuitable chute, spout or material delivery means I4. The bottom plate I5of the hopper I3 receives the direct delivery of material I6 from thechute I4 and as it piles up it rolls down the twin vertical deliverypassages I6, I1. In Figures 1 and 2, two of these passages are shown,diametrically opposed at an equal radial distance from the center ofrotation of the motor. Each of these spouts passes at its lower endthrough an aperture'l or I9 in the plate 5. AT'he weight of the spoutsmay be at least in part supported by flanges 20 welded or otherwisesecured to the lower ends thereof. Whereas we have shown in some of thedrawings vertical chutes or spouts it will'be understood, of course,that in the claims unless I limit myself specifically to the use ofvertical spouts, inclined spouts or chutes may be employed asillustrated, for example, in Figure 12.

Positioned within the member 6 is a ring 25. Enclosed within it is asecond and inner concentric ring 26. Between them is positioned a massor ring of rubber or any suitable equivalent mato serve as a-iloating`support for the shaft bearings. The rubber is confined in place as bythe bottom closure plates 28. The bolts 29 which hold it thus lock thefloating suspension in place. 30 is an outer rollenbearing race and 3Ian inner race, the rollers 32 being positioned therebetween. The innerraceis mounted;` upon the impeller shaft 9. It may, for example, beAlocked against the ledge 33 as Vby any suitable screw-threaded locking.ring 34. The ring 34 may have a downwardly extending flange 35 `lwhich455y overlaps the upwardly extending ange 36 of the plate 28. The resultis a species of labyrinth but it will be understood that any other meansmay be employed for keeping dust out of the bearings. To protect thebearings from above I illustrate a further closure plate 38 which en-Agages the enlarged portion 33 of the shaft 9. It may be provided withany suitable packing spaces 39.

Mounted on the lower end of the impeller shaft 9 is the impeller properwhich I illustrate in Figure 6 as a body 4|] having three projectingarms 4|. It may be keyed to the shaft 9 as by keys 42 and any suitablelocking means may be employed including the nut 43 as shown in Figure 2,for holding the impeller firmly in position upon the impeller shaft 9.Mounted in each of the arms 4| is an impact plate proper. I illustratethese plates in some detail in Figures 4 and 5. It is important thatthey be readily detachable. Referring to Figures 4, and 6,each

such plate includes a main impacting or body portion 50 with a forwardlyextending inner side portion 5|. Adjacent the juncture of 50 and 5|there is arearward piece which may be roughly described as a dovetail52, which penetrates a corresponding' aperture 53. It is clamped thereinas by a pair of wedges 54, 55, one being downwardly drawn and the otherupwardly by rotation of the oppositely screwthreaded bolt 56 .which isprovided at top and bottom with washers 51 and lock nuts 58. It will beunderstood that the bolt 56 can be rotated from either end by the squareend portions 59. Rotation in either direction moves the two wedges inrelatively opposite directions. The wedgesare half round in` form, asshown in Figure 4, and are provided with inclined faces 60, opposed tocorresponding faces 6| upon the member 50. The round portions of thebodies of the wedges seat ina rounded aperture 62 in the arm 4| which isreally a continuation Aof the dovetail aperture 53 or opens on one sideof it. Note that the impact surface of the member 5| is somewhat at anangle to that of the member 50. Also, the face of the member 5l) issomewhat inclined tothe true radius of the lmpeller. Furthermore, as isclear .in Figures 3 and 6, it is set somewhat at an angle in relation tothe axis of rotation of the impeller.

In order to have ready access to these impact .members I illustrate thecover 5 as provided with apertures closed by closure plates l0 which areremovably held in position as by bolts 1|, as shown in Figure 3.

Itw'ill be understood that a rotation of the impeller will carry thefacesof the member 50 at a high rate of speed through the path of thematerial dropping down the chutes |6 and whereby the particles, `fallingfreely under gravity, are impacted and are violently delivered n along agenerally horizontal direction. The first stage of reduction takes placeby this impact, as the particles fall. The second stage reductionresults from the impacting of these particles against xed wear plateswithin the base or housing .2.

Referring, for example, to Figures 1 and 6, in

the form of my device in which I employ an impeller with three arms inconnection with two chutes, the material isV impacted at two points bythe impeller and is therefore delivered centrifugally outwardly alongtwo separate paths or in bevelledalong their edges as at 8| and arewedged at their opposite edges as by wedges 82`control1ed by bolts 83which can be exteriorly actuated. The result of tightening the wedges 82i's to wedge the bevelled edge 8| firmly against the opposed portion 84of the base 2.4 As the material is not delivered along a strictlylimited path I provide a side plate 85 which is held in position as bybolts or screws 86. Top plates 81 are also employed, shown in dottedline in Figure 1 which are held in position as by bolts or screws 88.All the bolts and screws above described are accessible from theoutside. However, in order to get access to the bolts forinsertion orremoval of the plates I provide removable top closure plates 89 whichare held in position. by the bolts or screws 90 whereby ready access maybe had to the wear plates 80 and 85.

- Referring to Figure 7 I illustrate a variant form of the device inwhich three chutes are indicated -as 95, 96 and.91,' evenly spaced aboutthe path of the impeller. The impeller is provided with two arms 98 and99 respectively. This reverses the arrangement of Figure 1 in whichthere were more impact members on the impeller than spouts. A widelatitude of arrangement is possible but it is important that the spoutsand impeller members be of different numbers so that only one impact isbeing delivered at a time. In other words, whether two impact membersare employed on the impeller or three; they are preferably so related inrelation to the position and number of the chutes, that,only oneimpeller is delivering a crushing impact at a time.

It will be noted that the capacity of the impact crusher is in directproportion to the number` of chutes conveying the material down into thepath of the`impa'ct members 58 of the impeller. While the number ofchutes is limited to an economical maximum, they may be so arranged thatby doubling the number of chutes the capacity of the crusher may therebybe doubled. 'I'his may undersome circumstances indicate that two streamsof falling material may be impacted at the same time. Inasmuch as thereis a fixed loss of power due to windage and friction, the advantage ofincreasing the number of chutes is to crush more material with theexpenditure of power necessary to do such crushing and with little ifany increase in unproductive power. It will be understood that thenumber of impeller arms or members may be chosen to suit the speed ofthe impeller and the number of chutes, and does not directly affect thecapacity of the crusher. 'I'he capacity of the crusher is increased byincreasing the number of chutes, not the number of impact members, butwhen the number of chutes has been selected, the number of impellermembers 50 employed to get the desired result depends not merely uponthe number of chutes but also the speed of rotation of the shaft 9.

Referring to the form of Figures 8, 9 and 10, I vary the arrangement ofthe Vform of Figure 1 and following by adding means for causingpreviously crushed oversized material to fall downwardly across the faceof the Wear plates 86. I

illustrate, for example, separate feeding means for fine and coarsematerial. 00 is the feed box for the coarse material, which is incommunication with the two vertical' spouts |6 and |0| is a spout fordelivering previously crushed oversized material, for example screeningsfrom the first pass through the machine. It delivers to a line.

feed box |02 which is shown as having two after it is piled up on theseshelvesfdrops down the final spout or delivery space and falls therebydirectly across the face of the wear plate 80. Therefore, as shown inFigure 10, the particles delivered from the impact surfaces 50, as at Ain Figure are directed against the gravitally falling particlesindicated at B in Figure 10. These in the form of a sheet of neparticles, are

; therefore crushed against the plate 00, and re- A`ceive a furtherreduction. This form of the devi is particularly adapted to closedcircuit crushing and it will be understood that any eilicient form ofconveying and screening may be employed, whereby certain desiredintermediate sizes of material, liner than the original kfeed butcoarser than the desired end product, are dropped in front of the plateA for a further secondary impact.

Figure 11 illustrates a gariant form of my de- A vice in which the partsare transposed in such fashion that the motor housing 0 and itsassociated partsis positioned below the base 2. Any suitable dischargechutes H0 are illustrated, ioimed in what may if desired vbe a slottedbase It will be realized that whereas I have, described and shown apractical and operative device, nevertheless many changes may be made inthe size, shape, number and disposition of parts without departing fromthe spirit of my invention. I

therefore wish my description and drawings to be taken as in a broadsense illustrative'and diagrammatic rather than as limiting me to myspecific showing.

Referring to the form of device shown in Figure 12 I illustrate inclinedchutes or spouts Ilia which are adapted to direct the materialdownwardly toward the revolving impeller in a direction opposite to thatof the rotation of the impeller, to produce better reduction incrushing.

The impacted falling particles are affected not merely by the directspeed of rotation of the impact members 50 but by the additional lateralspeed, in an opposite direction, caused by their delivery into .the zoneof impact in a direction opposite to that of the rotation of theimpeller. Even an angle of degrees from the vertical will produce ahorizontal component of a considerable amount at the timethe materialleaves the bottom of the chute and enters the' zone of impact.

Any satisfactory means may be employed for.

counterbalancing the impeller. 'Either the impeller arms supporting themembers 50 are so distributed about the axis of rotation of theimpeller. as to maintain dynamic balance during rotation, or the partsmay be weighted in any suitable fashion in' order to prevent anyundesired vibration resulting from the high speed rotatio of theunbalanced member.

It will be understood that my device is particularly adaptable to closedcircuit crushing. 'Ihe product delivered gravltally downwardly from thecrushing zone, for example, falling freely downwardly away from thefaces of'the plates 80 and 85 or the overhanging plate 01 may be takenin any suitable conveying and screening means. 'I'he nes may beseparately disposed of and the oversized returned for recrushing. In theform of Figure 9 I illustrate means for recirculating some of theintermediate sized material by dropping it across the face of the plates80. This is under some circumstances desirable but motor shaft servingas'r the impeller vor impact shaft.

I might find one `impact occur.sirriultarie ouslyvl and forexempliilcation I` have illug'tijgt/egiin Figure 12 both the impactmembers 50'," Y leimpeller 49 and the delivery chutes I6, I1v'ametrically opposed to each other in relation* the axis of the shaft9. It will be understood, however, that I may vary the number of arms 4|and' associated impact members 50 and the number of chutes. Owing to thegreater unevenness of torque, because of a p rality ofsimultaneousimpacts, I may incorporat. in conjunction with the impeller40 `a ily wheel to eliminate heavy pulsation in the electrical circuitfor actuating the motor. y However, the greater the number of impactarms 4| and number o f chutes, the less this effect would be felt.

For slow running motors4 a greater number of impeller arms 4| may beemployed. For example, in connection with an impeller having two impactmembers 50 diametrically opposed to each other, flve delivery chutesequally spaced radially may be employed for delivering. asingle crushingimpact at a time, and, in the variant form illustrated in Figure 12,four delivery chutes may be used. In order to obtain a better crushingeffect I may deliver the material to be crushed at an angle towards therevolving impeller as illustrated in Figures 13 and 14. The chutes I2|herein shown as mounted at an incline, say for example at an angle ofabout 15 degrees with the vertical, direct the gravitally fallingparticles in a direction opposed to that of the revolving impeller.

The use and operation of my invention are as follows:

-Referring to the form of Figure 1 and following, I drop material bygravity freely along a plurality of paths, for example, along the chutesI6 and I1. Referring \to Figure '7, I increase the number of paths tothree, the chutes 95, 96 and 91. In both forms I employ an impellerhaving a plurality of impact members 50. These are ro tated by'. anysuitable motor at a high rate of speed. The rate of rotation may, forexample, be as high as 1500 R. P. M. It is important that the vrotor orimpeller be rotated at such a rate 2,086,383. 3 spouts |03 and IBIrespectively, to supplemental it is not an inseparable feature of mydevice. .In feed boxes |05, |00, with ledges or shelves |01 to] allforms of the device it will be noted/the motor' "break the fall of thematerial. The material,J is positioned closely ladjacent the impeller,the

that every particle which is impacted is so struck as tobe shattered. Inpractice, the effect is almost that of an explosion of the particle. Itis also important that the speed of drop of the material, as it entersthe impacting zone, is' such that each particle is carried fully orsubstantially fully into the path of the impact members 50, so as tovbestruck by a full face blow. For example, I find that chutes of a heightof say eight to ten feet are satisfactory. It will be understood,

of course, that a substantial variation may be made both in the speed ofrotation of the im# pact members and in the height ofthe drop. It isimportant that the material drop freely and without packing. H

By having themotor coupled directly to the impeller I avoid thenecessity of the use of any intermediate drive, gear reduction. orthelike. The rubber blocks 21 serve as, #vibration pre- .venting.means. Thewear plates 80 and V05 are readily removed and access to them and to theimpeller members is easilyhad by removal of the cover plates 10 and 80.4

I claim:

1. In an impact Crusher, a base, a rotor mounted upon said base torotate about a vertical axis, a plurality of impact members peripherallyspaced about said rotor, the impact face of said members having asurface Whose vertical dimension is of the same order as its horizontaldimension, a plurality ofV substantially vertical feed spouts adapted todeliver material, at widely spaced points, to the path of movementvofsaid impact members, and individual secondary fixed crushing plateslaterally aligned with the zone of intersection of the path of feed fromeach spout with the path of movement of the impact members of the rotor,said secondary impact members being sufficiently spaced laterally fromthe path of movement of the rotor to permit the secondarily crushedparticles to fall gravitally along a path removed from the path ofmovement of the impact members.

2. In an impact crusher, a base, a rotor mounted on said base forrotation about a generally vertical axis, means for rotating said rotor,a plurality of impact members mounted on said rotor and spacedperipherally thereabout, and a plurality of generally vertical tubulardelivery chutes adapted to deliver the material to be crushed at thegeneral level of and in the path of movement oi said impact-members, ata plurality of segregated delivery zones, one for each tance from therotor to permit the secondarlly impacted particles to drop by gravityalong a path removed from the zone of the primary impacting.

3. 'Ihe structure of claim 2 characterized by lthe employment of adifferent number of impact members and chutes.

4. The structure of claim 2 characterized by the employment of aplurality-of chutes and of a greater number of impact members than ofchutes.

5. The structure of claim 2 characterized by the positioning of thechutes, in relation to the distribution of the impact members about therotor, in such fashion that the delivery from each chute is impacted ata time when the delivery from no other chute is being impacted.

6. The structure of claim 2 characterized by the employment of separateand distinctsecondary impact members each positioned to receive theparticles discharged from oneof said chutes, after their impacting bythe rotor.

'7. The structure of claim 2 characterized in that the .secondary impactmembers are so spaced vin relation to the primary impact members thatthe ensuing delivery from the primary impact members of impactedparticles causes a bombardment of the particles already impacted againstthe secondary impact members.

8. The structure of claim 2 characterized vby the employment of chuteswhich are inclined somewhat against the direction of rotation of therotor, whereby the particles are delivered for crushing in a direction-opposed to the direction of rotation of said rotor.

9. The structure of claim 2 characterized by, the employment of a likenumber of delivery' chutes and impact members.

' 10. The structure of claim 2 characterized by the employment of agreater number of impact members than of chutes.

' OSCAR C. GRUENDER.

